White-Winged Flufftail, Sarothrura Ayresi
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White-winged Flufftail, Sarothrura ayresi © Henok Samson Compiler: Bruktawit Abdu Mahamued Contributors: Samson Zelleke, Henok Samson, Claudia Gray, Caleb Ofori Suggested citation: Mahamued, B.A., Zelleke, S., Samson, H., Gray, C. and Ofori, C. 2020. A Survival Blueprint for the conservation and management of the White- winged Flufftail, Sarothruraayresi, in Ethiopia. An output from the EDGE of Existence fellowship, Zoological Society of London. 1. STATUS REVIEW 1.1 Taxonomy: Sarothruraayresi (Gurney, 1877) Class: Aves Order: Gruiformes Family: Rallidae Genus:Sarothrura Species: ayresi Common Name: White-winged Flufftail The White-winged Flufftail (Sarothruraayresi) was first described in 1877 by Gurney as Coturnicopsayresiin South Africa (Dowsett and Forbes-Watson, 1993). It was later placed in the genus Sarothrura (Heine, 1890). Sarothruraayresiisunder the Order Gruiformes and the Family Rallidae (del Hoyo et al., 2014). The birds in Ethiopia were first described in 1911 by Bannerman as Ortygopsmacmillani(Sibley and Monroe, 1993). The bird is also called the White-winged Crake. In Oromiffaa, the local language spoken in the regional state where the bird occurs in Ethiopia, (Berga), it is referred to as Simbirro Bargaa, which is literally translated as the bird of Berga. Berga is the name of the river that runs through the birds’ wetland habitat at this locality. The genus Sarothrura comprises seven speciesthat are all found in Africa. Sarothruraayresi is the only flufftail with white wing patches on its inner flight feathers or its’ secondaries. The adult males have a chestnut head, upper back and breast, while in the female this colouration is restricted to the neck and sides of breasts (Keith, 1986). Both sexes have a black-barred chestnut tail and white wing-patches on the secondary flight feathers(Redman et al., 2009). 1.2 Distribution and population status: The species (Sarothruraayresi) is known to occur in South Africa, Zimbabwe and Ethiopia. The birds in Ethiopia were first described in 1911. The species was known from Sululta plain in Ethiopia in the 1930s and 1940s. Sululta is in Oromia region, Central Ethiopia about 20km north of Addis Ababa. Sarothruraayresi was re-discovered again in 1995 in Sulultain a certain locality called Weserbi. Their breeding was confirmed in July and August of the same year at the Weserbi locality (Atkinson et al., 1996). Due to this reason the Sululta site was designated as an Important Bird Area in 1996. However, the species has not been found there in recent times (Tilahun et al., 1996). In 1997, several breeding pairs (about 200) of the White-winged Flufftail were found in the Berga wetlands. Berga is in Oromia region, Central Ethiopia about 70km west of Addis Ababa. The Berga site was soon designated as an Important Bird Area (IBA) following this significant finding of the species at the site. During 1999, the first nest was found in the area further confirming that it is breeding at this site. The Berga wetlands continues to be an important stronghold for the species even in recent years. The species has also been found in Bilacha located in Oromia region, Central Ethiopia, close to the Berga wetlands. In 2017 and 2018, a couple of pairs and one nest was found at Bilacha while conducting surveys as part of my EDGE fellowship activities. However, in 2019 we were not able to find a single individual or any signs of its’ breeding activities at this site. During the 2019 survey, we realized that the area had been grazed very low and disturbed as compared to the previous years. The White-winged Flufftails seen in Ethiopia and South Africa were recently found to be the same population (Dalton et al., 2017). The current estimate of the global population of the species is less than 250 individuals (BirdLife International, 2015) which has resulted in the upgrade of the species IUCN Red List status to Critically Endangered since 2013 (BirdLife International, 2018). 1.2.1 Global distribution: Country Population Distribution Population trend estimate (plus references) (plus references) Ethiopia 50 – 249 individuals Oromia region Decreasing (BirdLife International, (BirdLife 2020) International, 2020) South 50 – 249 individuals Middlepunt wetland, Decreasing (BirdLife International, Africa (BirdLife Wakkerstroom, 2020) International, 2020) Steenkampsberg and Bedford wetland Zimbabwe 50 – 249 individuals Harare (Monavale, Decreasing (BirdLife International, (BirdLife Marlborough) 2020) International, 2020) Zambia 50 – 249 individuals Chingola, Solwezi? Decreasing (BirdLife International, (BirdLife 2020) International, 2020) 1.2.2 Local distribution: Country Region / Site Level of Population Reference(s) Notes province Protection size Ethiopia Oromia Berga IBA with no 50 – 249 (BirdLife Birds still protection individuals International, present at 2020) current time Ethiopia Oromia Bilacha No Not known The bird has protection not been recorded since 2018. Ethiopia Oromia Weserbi IBA with no Not known No recent protection records since late 1990s 1.3 Protection status: Since the realization that Ethiopia is an important site for the species, the Ethiopian Wildlife and Natural History Society (EWNHS) along with the Middlepunt Wetland Trust and BirdLife South Africa have initiated several research and conservation works at the Berga site. This has resulted in the advancement of knowledge about the species, community development work in the area including the digging of new water wells, construction of a school, and the establishment of a strong Site Support Group (SSG) at Berga. An SSG is a local conservation group that is usually set up by BirdLife International partners in order to conserve a threatened bird species and its habitat. In this particular instance, the SSG undertake several conservation activities such as protecting the core habitat of the species by making sure that grasses in these core habitat areas are not harvested during the birds breeding season. The SSG also helps to raise awareness about the species in the local community. Two of the sites (Berga and Weserbi) in Ethiopia are Important Bird Areas but do not have legal protection. At Berga, some 400 hectares of land is owned by the Holeta Agricultural Research Centre, which is used for breeding cattle. The organization does not allow grazing on this land from June until December, which synchronizes with the time the species inhabits Ethiopia. The rest of the grasslands are unregulated communal and private grazing areas. Weserbi has become quite degraded over recent years and is therefore not suitable for the species. Unless grazing pressure is significantly reduced, this site will no longer be able tos upport the species into the future. Bilacha is a relatively small area and it is mostly communal grazing land with some fenced off private grazing areas. Some individuals who own small pieces of the wetland have erected fences to prevent other cattle from grazing on private property (land) and not necessarily to protect the bird’s habitat. 1.4 Ecology, behaviour and habitat requirements in Ethiopia: Behavior– The White-winged Flufftail is a secretive and a very small bird measuring about 14cm and weighing about 30gm (Redman et al., 2009). They are ground-nesting birds that forage by cryptically moving through longer grasses, which makes it difficult to see them (Sande et al., 2008). They usually flush when approached (Allan et al., 2006). This is the main means of detecting the species whilst undertaking surveys although they may also be spotted through nest encounters. During the EDGE fellowship, it was observed that the birds aggressively defend their nest when incubating. They display aggression by showing the white patches on their wings and charging towards the intruder whilst making hissing sounds in the process. Habitat requirements – In Ethiopia, the species occurs in seasonally flooded vegetation (Sande et al., 2008)in high altitude wetlands above 2,000 meters above sea level. According to data gathered at Berga as part of this EGDE fellowship activities(2018, 2019), the White- winged Flufftails were found in areas with mean water level of 5.45cm (Table 1). It appears that the species preference for water spans from as low as 2cm to as high as 8cm. The species is usually found in areas with taller grasses (mean grass height of 30.69cm and a range of 25 - 35cm). Regarding their preference or tolerance of bare ground, we have found the Flufftail mainly in areas with 10 to 18% bare ground coverage. Table 1. The mean, standard deviation, min and max values of the habitat variables measured at Berga, Ethiopia, in locations where the White-winged Flufftails were sighted. Water Level (cm) Grass Height (cm) Bare ground (%) Mean Value 5.30 30.69 14.92 Standard 3.89 8.34 8.23 Deviation Max 12 45.67 40 Min 0 16.67 5 Regarding the vegetation types, the Flufftails were found in areas that had a combination of grass and sedge species. There were 13 species of plants that were found in the vicinity of Flufftail habitat. Eight of the most commonly found plant species are listed in Table 2. Ashufe, Balemi, Chefe Guba, Kuni and Chilimoare found in higher abundance in the sites where the White-winged Flufftail has been recorded, indicating their suitability for the species. Table 2.The local and scientific names of plant species mainly seen in Berga where White- winged Flufftails were sighted. Local name (Oromiffa) Scientific name 1. Ashufe Eragrostis tenuifolia 2. Balemi Andropogon dummeri 3. Chefe Guba Ranunculus multifidus 4. Kuni Cyperus rigidifolius 5. Chilimo Cyperus atronervatus 6. Buski Cyperus dichrostachyus 7. Amakyta Trifolium wartinianum 8. Welebo Crinium abyssinicus 1.5 Threat analysis: Threat Description of how this threat impacts Intensity of the species threat (low, medium, high, critical or unknown) Habitat loss and degradation Expansion of Agriculture including Critical eucalyptus plantations is one of the main causes of the loss of the species habitat. Subsequent soil erosion following habitat conversion decreases the availability of good quality grass species that the Flufftail can use to feed and/or to nest.